Horner visited the town and recognized the remains as belonging to a duck-billed dinosaur.
He announced the find of remains of at least ten duck-billed dinosaurs in western South Dakota.
Nearer the water, some duck-billed dinosaurs with long crests rising above their heads moved forward to drink.
Anatotitan is one of the largest and most famous duck-billed dinosaurs (called hadrosaurs).
What do a horse, a brook trout, a honeybee and a duck-billed dinosaur have in common?
Ilona's initial discovery turned out to be a duck-billed dinosaur.
Hadrosaurids, or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae.
As this sea began to withdraw a new subtropical coastal plain environment which was home to duck-billed dinosaurs spread across the state.
The findings also include the remains of a 20 meter (66 ft) hadrosaurid, a record size for the duck-billed dinosaur.
The maiasaur was a plant-eating genus of duck-billed dinosaur, which grew to about 30 feet.